# 计科201132叶英杰
score = int(input("请输入学生的百分制成绩："))
if score >= 90:
    print("五分制成绩：A")
elif score >= 80 and score < 90:
    print("五分制成绩：B")
elif score >= 70 and score < 80:
    print("五分制成绩：C")
elif score >= 60 and score < 70:
    print("五分制成绩：D")
elif 0 <= score < 60:
    print("五分制成绩：E")
else:
    print("输入错误")